What factors determine whether an application should use a monolithic architecture?

What factors determine whether an application should use a monolithic architecture?

A monolithic architecture packages much of an application's server-side functionality into one deployable application. It can be a practical starting point when a small team needs to deliver connected features without operating many independent services.

Consider the team's actual needs

A wedding-management MVP may have one team building events, tasks, and guest invitations on a shared schedule. Keeping those modules in one application can simplify local development, testing, and deployment.

The decision should consider expected traffic, deployment frequency, operational experience, and how closely features depend on each other. A requirement to support many users does not automatically require microservices; measure the relevant workload and identify real bottlenecks.

Preserve boundaries inside one application

A monolith does not require putting every operation in one large file. Separate event management, task handling, invitations, and access control into understandable modules. Give each module clear interfaces and ownership of its business rules.

For example, the invitation module should call a defined email-delivery interface instead of scattering provider calls throughout page components. That boundary improves testing today and makes a future change easier.

Compare the costs of separation

Independent services introduce network failures, coordination between deployments, distributed logs, and more infrastructure. They can be justified when teams need independent ownership or a workload needs a distinct runtime or scaling strategy.

Ask AI to compare a modular monolith with a separated architecture using your constraints. Require it to explain which concrete problem each extra service solves. Record the initial decision, the assumptions behind it, and measurable conditions that would justify splitting a module later. A clear path to change is more useful than speculative complexity.